Nasal surgery handled by CFD tools.

Annually, hundreds of thousands of surgical interventions to correct nasal airway obstruction are performed throughout the world. Recent studies have noted that a significant number of patients have persistent symptoms of nasal obstruction postoperatively. In the present work, we introduce a new methodology that raises the success rate of nasal cavity surgery. In this procedure, the surgeon performs virtual surgery on a 3D nasal model of a patient prior to the real surgery. The main goal of the methodology is to guide the surgeon throughout the virtual operation using mathematical estimators based on CFD results. The virtual surgery intervention ends as soon as the estimators fall into a region of a Cartesian coordinate system with a high success probability. This region is defined according to a statistical analysis of estimators corresponding to sets of healthy and diseased cavities. As examples of this application, this study includes 2 surgical operations performed with this innovative methodology on patients with severe nasal obstruction. The patients underwent nasal surgery according to the final nasal geometry revealed by CFD-guided virtual surgery. Currently, both subjects show high degrees of satisfaction.

Cirugía virtual para pacientes con obstrucción nasal: empleo de un software basado en dinámica de fluidos (MeComLand(R), Digbody(R) & Noseland(R)) para documentar parámetros objetivos de flujo y optimizar resultados quirúrgicos / Virtual surgery for patients with nasal obstruction: Use of computational fluid dynamics (MeComLand(R), Digbody(R) & Noseland(R)) to document objective flow parameters and optimise surgical results

INTRODUCCIÓN: La dinámica de fluidos computacional (CFD) es una herramienta matemática que permite analizar el flujo aéreo. Presentamos un software innovador basado en CFD para mejorar los resultados de la cirugía nasal. MÉTODOS: Mediante colaboración de ingenieros especialistas en mecánica de fluidos y otorrinolaringólogos se ha desarrollado un software de fácil uso denominado MeComLand(R), que utilizando los cortes de tomografía computarizada de un paciente permite obtener gran cantidad de información como flujo, presiones, temperatura, velocidad o fricción sobre la pared de las fosas nasales. El programa DigBody(R) permite modificar en 3 D la anatomía del modelo y realizar cirugías virtuales para simular resultados antes de la cirugía real. Por último, NoseLand(R) permite viajar virtualmente por el interior de la fosa nasal, mostrando todo tipo de magnitudes termo-fluido mecánicas. OBJETIVO: Presentar un programa innovador para mejorar los resultados de la cirugía nasal. Emplear este software sobre cortes tomográficos de un paciente con desviación septal para planificar distintas opciones quirúrgicas (septoplastia, turbinectomía, spreader-grafts, colgajo en J y combinaciones) a fin de conseguir la mejor alternativa con la menor morbilidad. RESULTADOS: La combinación de todos los procedimientos considerados no produce los mejores resultados en cuanto a flujo nasal. Estos se consiguen asociando septoplastia y turbinectomía. La turbinectomía aislada obtuvo resultados muy similares a la septoplastia. CONCLUSIONES: La técnica computacional CFD proporciona una información complementaria valiosa en el diagnóstico del paciente con obstrucción nasal y sobre los resultados de distintas alternativas quirúrgicas respecto al flujo nasal, contribuyendo a un mejor manejo del enfermo. El software MeComLand(R) con sus respectivos módulos DigBody(R) y NoseLand(R) suponen una alternativa barata y no invasiva al estudio funcional del paciente con obstrucción nasal

INTRODUCTION: Computational fluid dynamics (CFD) is a mathematical tool to analyse airflow. We present a novel CFD software package to improve results following nasal surgery for obstruction. METHODS: A group of engineers in collaboration with otolaryngologists have developed a very intuitive CFD software package called MeComLand(R), which uses the patient's cross-sectional (tomographic) images, thus showing in detail results originated by CFD such as airflow distributions, velocity profiles, pressure, or wall shear stress. NOSELAND(R) helps medical evaluation with dynamic reports by using a 3D endoscopic view. Using this CFD-based software a patient underwent virtual surgery (septoplasty, turbinoplasty, spreader grafts, lateral crural J-flap and combinations) to choose the best improvement in nasal flow. OBJECTIVE: To present a novel software package to improve nasal surgery results. To apply the software on CT slices from a patient affected by septal deviation. To evaluate several surgical procedures (septoplasty, turbinectomy, spreader-grafts, J-flap and combination among them) to find the best alternative with less morbidity. RESULTS: The combination of all the procedures does not provide the best nasal flow improvement. Septoplasty plus turbinoplasty obtained the best results. Turbinoplasty alone rendered almost similar results to septoplasty in our simulation. CONCLUSIONS: CFD provides useful complementary information to cover diagnosis, prognosis, and follow-up of nasal pathologies based on quantitative magnitudes linked to fluid flow. MeComLand(R), DigBody(R) and NoseLand(R) represent a non-invasive, low-cost alternative for the functional study of patients with nasal obstruction

Virtual surgery for patients with nasal obstruction: Use of computational fluid dynamics (MeComLand®, Digbody® & Noseland®) to document objective flow parameters and optimise surgical results. / Cirugía virtual para pacientes con obstrucción nasal: empleo de un software basado en dinámica de fluidos (MeComLand®, Digbody® & Noseland®) para documentar parámetros objetivos de flujo y optimizar resultados quirúrgicos.

INTRODUCTION: Computational fluid dynamics (CFD) is a mathematical tool to analyse airflow. We present a novel CFD software package to improve results following nasal surgery for obstruction. METHODS: A group of engineers in collaboration with otolaryngologists have developed a very intuitive CFD software package called MeComLand®, which uses the patient's cross-sectional (tomographic) images, thus showing in detail results originated by CFD such as airflow distributions, velocity profiles, pressure, or wall shear stress. NOSELAND® helps medical evaluation with dynamic reports by using a 3D endoscopic view. Using this CFD-based software a patient underwent virtual surgery (septoplasty, turbinoplasty, spreader grafts, lateral crural J-flap and combinations) to choose the best improvement in nasal flow. OBJECTIVE: To present a novel software package to improve nasal surgery results. To apply the software on CT slices from a patient affected by septal deviation. To evaluate several surgical procedures (septoplasty, turbinectomy, spreader-grafts, J-flap and combination among them) to find the best alternative with less morbidity. RESULTS: The combination of all the procedures does not provide the best nasal flow improvement. Septoplasty plus turbinoplasty obtained the best results. Turbinoplasty alone rendered almost similar results to septoplasty in our simulation. CONCLUSIONS: CFD provides useful complementary information to cover diagnosis, prognosis, and follow-up of nasal pathologies based on quantitative magnitudes linked to fluid flow. MeComLand®, DigBody® and NoseLand® represent a non-invasive, low-cost alternative for the functional study of patients with nasal obstruction.